A new study by a team of international researchers has for the first time “explicitly revealed” uranium and other radioactive materials in the surrounding environment of the damaged Fukushima Daiichi nuclear reactors following the nuclear accident at the site in 2011.
In a study published in the journal Environmental Science & Technology last month based on research conducted by an international team of scientists, explicit evidence of uranium and other radioactive materials — such as caesium and technetium — have been found in the surrounding environment of the Fukushima Daiichi nuclear reactors after being released from the damaged reactor.
We have to turn our attention all the way back to March of 2011 when the magnitude 9 Tōhoku earthquake unleashed a tsunami on the east coast of Japan which, unfortunately, caused an accident at the Fukushima Daiichi Nuclear Power Plant. A cascade of issues resulted in three nuclear meltdowns, hydrogen-air explosions, and the release of radioactive materials from Units 1, 2, and 3.
Ever since, scientists have been keenly observing the site and its surrounding environment for signs of nuclear radiation, and it was almost a year ago that we received our first direct images of the damaged nuclear fuel rods.
The new study published last month, however, focuses further afield from the Fukushima Daiichi Nuclear Power Plant in the search for nuclear materials. While there have been various discoveries in the immediate vicinity of the nuclear meltdown, this is the first time that nuclear reactor fuel debris has been “explicitly revealed” in the surrounding environment, which means that the impact from the fallout might last much longer than had previously been expected.
Among the international team of scientists were experts from The University of Manchester, who explained their research late last month:
“The scientists have been looking at extremely small pieces of debris, known as micro-particles, which were released into the environment during the initial disaster in 2011. The researchers discovered uranium from nuclear fuel embedded in or associated with caesium-rich micro particles that were emitted from the plant’s reactors during the meltdowns. The particles found measure just five micrometres or less; approximately 20 times smaller than the width of a human hair. The size of the particles means humans could inhale them.”
“Our research strongly suggests there is a need for further detailed investigation on Fukushima fuel debris, inside, and potentially outside the nuclear exclusion zone,” further explained Dr Gareth Law, Senior Lecturer in Analytical Radiochemistry at The University of Manchester, and an author on the paper. “Whilst it is extremely difficult to get samples from such an inhospitable environment, further work will enhance our understanding of the long-term behaviour of the fuel debris nano-particles and their impact.”
Prior to this most recent research, it had been assumed that only volatile, gaseous radionuclides such as caesium and iodine were released from the damaged reactors. However, the new research is clarifying that small, solid particles were also emitted from the fallout and that some of these particles contain long-lived radionuclides.
How long lived is “long lived”? Uranium, for example, has a half-life of billions of years.
That doesn’t bode well.